Freira, SilviaFonseca, HelenaWilliams, GeoffreyRibeiro, MartaPena, FernandaMachado, Maria do CéuLemos, Marina Serra2020-10-262020-10-262019Patient Education and Counseling 102 (2019) 718–7250738-3991http://hdl.handle.net/10451/44666© 2018 Elsevier B.V. All rights reservedTo compare motivational interviewing (MI) with conventional care regarding the health-related quality-of-life (HRQoL) of adolescents with overweight/obesity. Methods: RCT with parallel design, involving two groups: intervention group (MI group [MIG]) and control group (conventional intervention group [CIG]). The intervention included three 30-minute interviews 3 months apart. Outcome: Change in Pediatric Quality of Life Inventory (PedsQL) scores. A mixed repeated-measures analysis of variance was used to assess group versus time interactions. Results: Eighty-three participants finished the protocol (82% girls). MIG participants showed a significant average increase (+4.7) on the Psychosocial (t[41] = -2.388, p = .022, d = .37) and Emotional Subscales (+5.1) (t[41] = 5.733, p < .001, d = .88). CIG participants showed a significant average decrease on the Psychosocial (-6.1) (t[40] = 5.733, p < .001, d = .90), Emotional (-14.1) (t[40] = 7.249, p < .001, d = 1.13) and Social Subscales (-3.8) (t[40] = 3.782, p = .001, d = .59) and on the Total Score (–4.4) (t[40] = 3.535, p = .001, d = .55) Conclusion: MI improved HRQoL among overweight adolescents participating in a weight management program. Practice implications: MI increases HRQoL and has the potential to benefit weight management programs for adolescents.engAdolescent obesityCounselingLifestyleSchool health servicesWeight lossMental healthjournal article10.1016/j.pec.2018.11.011